Biochemical procedures involving sequential reactions, such as for example, oligonucleotide synthesis, oligonucleotide sequencing reactions, peptide and polypeptide synthesis, and sequential binding assays, have spawned a body of technology aimed at automating the procedures. The purpose of these developments has been to reduce the time required to perform the sequences, as well as to achieve uniformity in the manner in which the sequences are performed, thereby permitting large numbers of sequences to be performed simultaneously and eliminating the potential for human error.
Sequential reactions of this type are commonly performed by immobilizing a species on a solid phase support and bringing the immobilized species in contact with a series of liquid solutions containing the reagents or reactants needed to perform the reactions. The prior art includes a variety of system configurations for achieving this, whereby the solid phase is retained in receptacles such as wells or columns and the movement of liquids into and out of contact with the solid phase is achieved by automated valves or syringes.